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I decided to start a build thread for my project to document and share the process. I hope to get some valuable insite from forum members and maybe it will help someone else along the way. My car is a 1973 240Z I’ve owned since 1986, my high school car. I recently brought this old girl in to give her a full makeover. The plan is a Pro-Touring/G-machine type build. This will not be a stripped down race car. There are some excellent examples here and I really respect those builds but that is not what I am after. I want something with breath taking performance and extremely light weight. No, I won’t be using full carbon body work and titanium fasters. I’d love to but the project needs somewhat of a budget. I will be using top quality parts and materials. Fiberglass and 4130 aren’t out of the question.

Ok, for the driveline. I’ll get this out of the way and just say to all of those out there that yes, it would be easier to just do an LS. I intimately familiar with the engine, controls, all of it and had originally planned on using a really healthy LS3 based engine. That said, I have always loved the sound and visceral feel of and high revving engine that is in there. I have a 2.6L (280 block, 240 crank) with triple DCOE Webers, Tri-Y exhaust, ported, balanced, cammed, etc. engine. I would like to keep those two traits with 3 times the power in a lightweight excellent handling package. I know there are Nissan purists or other import options out there. I respect those builds too. However, Ford had to go and introduce a new flat plane crank engine “Voodoo” version of the Coyote. So, as much as I have never been a Ford guy, this new engine is just too good to pass on. So, Voodoo it is with a Tremec T56 Magnum 6 speed and a "new version" 8.8 in the rear. I will be doing full upgrades of chassis, suspension, paint, and the works. She needs to be comfortable so power windows and locks and a replacement HVAC including A/C that actually works. Weight will be minimized and safety addressed. Though not a track car, track days are in the vision and I will weigh out each option to best fit the intended vision.

I have the Tremec Magnum in the wide ratio version and Modular bellhousing. A Coyote may have to be used initially until the Voodoo is available at least semi reasonably priced. The Voodoo is based on a Coyote and with the right “buy” on a Coyote, I should be able to make money on the deal rather than lose on that. I would start with a truck Coyote, replace pistons, rods (already have a set of Manley “H” beams) and cams. The wiring and programming I would do myself on both. An aluminum 8.8 will be used with rear CV joints and shafts probably the Porsche 930/935 variety. Hubs will be aluminum or a lightweight unit bearing 5 lug and source will depend on the suspension choices.

Let me just get this out of the way this car is NOT the best starting point for a project. I will be doing complete floors, supports and front frame rails as well as a lot of bodywork. The car has been in at least 3 collisions and the salted roads and years have taken a huge toll. That said, she’s part of the family with a lot of memories attached and that means something to me. I have a rotisserie ready to assemble but will need to get everything at least straight and structurally sound enough to sit in the rotisserie before it goes on there. I will most likely be replacing the parts and tack welding in first then up to fully weld everything in. All the structure will be tied together front to back. I have debated buying the Bad Dog products or just fabricating things, maybe even out of 4130. I'm thinking of using 2x3 tubing up front then split for the supports along with thinner sheet for the floor and integrate that into the roll bar/cage/seat mounts as well as the transmission and differential mounts underneath. I'm thinking of integrating a scattershield into the tunnel rather than the bellhousing.

I will be doing flush glass (possibly MR10), shaved gutters and a lot of other “clean-up” details while I am in there. The bodywork will be a full set from John at ZTrix/Reaction Research consisting of Subtle Z fenders, air dam, hood, solid cowl, early style fiberglass bumpers, YZ rear fenders, doors, hatch, a 2-taillight (Ferrari tailights) rear cap and then a Motorsport Classic rear spoiler like the car has now but in fiberglass that may be built up a bit with a wickerbill. I have quite a few ideas for some clean venting and details formed into these parts. We’ll see where it goes. I’ll play with the aerodynamics as much as possible with the platform to get some solid downforce and clean things up where I can. Wheels and tires will be Michelin Pilot Super Sport 245/35R18 front and 295/35R18 rear on either a 5 or split 5 spoke wheel.

Brakes will be a Tilton/Wilwood style aluminum pedal setup with 3 remote reservoir master cylinders - no power assist. At the wheels will be 6 or 4 piston calipers and the biggest rotor on aluminum hats that I can make work. Possibly a Woodward aluminum column if I can make that do what I want. I will consider electric power steering but will replace the rack with a new aluminum version either way.

Suspension and hubs will be replaced with 5 lug aluminum or unit bearing versions. A double wishbone coilover setup just from the standpoint of I’m already re-doing all the structure anyway and it would be easier to adjust and get proper geometry. With the way all this is packaged I don’t know what the best way to set that part of it up will be yet.

Interior will have a new A/C unit, power windows and locks. Lizard skin soundproofing like I used on my last Jeep project. New gauges, probably Speed Hut, completely new wiring, console, etc. It will still be discernable as a 240Z but pretty much everything will be upgraded. I have 1-1/2” 0.095 wall 4130 for the roll bar/cage. I’m not sure yet how extensive that will get but it will tie everything in the back together and the forward part is not fully decided. I won’t do full door bars because the car will still be a driver but maybe a combination of the two. Sound system will be Polk MM6501 front, MM651 rear (neodymium magnet/composite cones - they weigh just over 1lb and have incredible sound) and a good head unit. Thinking the new Sony high power and do away with the amp and sub to save 20lbs. I have the 10” Alpine SWR-T10 Sub for my Jeep with the neodymium magnets but that with an amp still adds about 20lbs. On this car, that’s 4-5 horsepower, not sure it’s worth it, we’ll see. That engine should be music enough anyway.

This isn’t going to happen overnight but it will be done right. I have a climate conditioned, well-equipped shop/garage including MIG/TIG as well as Ocy/Acetylene, plasma cutter, sheet metal brake, tubing bender, etc. I can fab most stuff on site and have access to CNC machining as necessary. I’ve been at this stuff a long time. I appreciate feedback and suggestions but please don’t muddy up the thread with off topic or tactless comments.

I’m going to try and at least start this out in an orderly fashion. I’ll follow with posts detailing the systems of the car that I just wrote about. I don’t know how long the site will allow editing but I’ll keep these first posts up to date as long as I can.

Update: These appear to respond REALLY well to long tube headers, open exhaust and a tune. Mustang boys are reporting over 500rwhp with only minor adjustments so far, projecting over 600+ at the flywheel fairly easily.

Edited May 25, 2016 by jpndave

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Tremec T56 Magnum wide ratio with Modular Bellhousing. I chose the wide version because all of the ratio spreads are very close to the same and all easily fit in the Voodoo power band which is very wide. The first chart shows short shifting at the crossover for torque/hp which keeps it in the big flat area of the torque curve you can see above and the 2nd shifting at peak HP. 1st gear at redline would be 65 mph with 3.31 gears, 57 mph with 3.73. REM (smoother shifting at high RPM) and Cryo (strength, supposed to make them good for 1,000+ HP) gears. Blueprint trans with bronze shift bushings throughout. The Magnum already has the better syncros and other parts. Lightweight smaller diameter clutch and flywheel for less rotational mass. The Voodoo uses a dual mass flywheel, I'm not sure how much I can mess with that and not cause balance issues. Stock aluminum bellhousing which I have along with the transmission. Scattershield will be integral 4130 in the tunnel when the floors are replaced. The added weight just as well increase body stiffness and it needs replacing anyway.

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Good luck with your build. There are a number of contradictions in your plan but there always are any of these projects. Compromise is the name of the game. Focus on the ultimate goal when making the small decisions.

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That is a 3.73 with a Torsen T2R from a 2015-16 Mustang with the track pack. I would like to get an aluminum housing to save some weight but can mock up with this one and even run it a while if necessary.

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That's the beauty if that transmission with an engine that has a good powerband, it's always in the power up to way past where it will go. If I could muster a 200mph run it would be right at peak HP for the Voodoo. Not sure if 500 wheel HP would pull that off though. It would be fun to try - once anyway on the flats.

We should put one of these 8.8 diffs in your car. What ratio are you looking for?

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Look at the ears on that diff, mounting it under the Z is going to be a whole lot easier than the other style. Plenty of meat to avoid the thing climbing around under the car. They run 34 spline inners stock. Mustang upgrades are all over the place and honestly, the stock parts with shortened shafts should be plenty strong for the 1000-1500lb lighter Z cars. If you are ok with an iron main housing, 3.31 gears and a limited slip I can get one for a great deal for you!